Investigation of weld effective length rules for RHS overlapped K-connections

摘要

A laboratory-based test program was conducted to assess the performance of welds in rectangularrnhollow section (RHS) overlapped K-connections. A 10m span, simply-supported, RHSWarren truss wasrnfabricated with nine connections designed to be weld-critical with varied key factors that affect weld strength inrnRHS connections: branch member overlap, chord wall slenderness, and branch-to-chord width ratio. By meansrnof a point load applied to strategic panel points, sequential fracture of the welds to the overlapping branchesrnwas obtained. The normal strains adjacent to the welds around the RHS perimeter and branch axial loads werernmeasured. By using the mechanical and geometrical properties of the welds and RHS, the structural reliabilityrn(or safety index) of the existing AISC specification provisions for weld effective lengths in RHS overlappedrnK-connections was determined. The existing AISC 360-10 formulae were found to be conservative, and hencernmore liberal recommendations are proposed.